1220021111021 has 2 divisors, whose sum is σ = 1220021111022. Its totient is φ = 1220021111020.

The previous prime is 1220021110969. The next prime is 1220021111033. The reversal of 1220021111021 is 1201111200221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 849853515625 + 370167595396 = 921875^2 + 608414^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220021111021 - 2¹⁰ = 1220021109997 is a prime.

It is a super-2 number, since 2×1220021111021² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1220021110987 and 1220021111005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1220021111921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610010555510 + 610010555511.

It is an arithmetic number, because the mean of its divisors is an integer number (610010555511).

Almost surely, 2^{1220021111021} is an apocalyptic number.

It is an amenable number.

1220021111021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220021111021 is an equidigital number, since it uses as much as digits as its factorization.

1220021111021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1220021111021 its reverse (1201111200221), we get a palindrome (2421132311242).

The spelling of 1220021111021 in words is "one trillion, two hundred twenty billion, twenty-one million, one hundred eleven thousand, twenty-one".